This invention relates to tubulating a barrel, that is sealing a glass tube to a barrel and opening a hole through the barrel communicating to the inside of the tube. In particular, this invention relates to the construction of stopcocks including not only the standard two way stopcocks but also, T-Bore, 3-way and 4-way stopcocks.
The standard stopcock includes a glass barrel with a tapered machined surface on the inside through which a matching tapered cone-shaped plug interfits connected to a handle to turn the plug member. At least one hole is drilled through the plug member. Glass tubing is welded, to the sides of the barrel with holes through the barrel to align with the ends of the holes in the plug member. In the trade this tubulating process is known as "sealing the tubing". Stopcocks and like parts are constructed in a variety of ways and of tubulating the barrel is a continuing problem. The holes have been drilled out, pulled out or burned out with a gas torch. Drilling sets up strains in the Pyrex or quartz glass of the barrel and produces particles which interfere with processing and must be scrupulously removed. Burning out or pulling out holes in a glass requires substantial heat sometimes deforming the barrel and yielding a high reject rate.
There is a real need for an apparatus and method for producing stopcocks at a high rate of speed under conditions that will provide few rejects due to distortion or stray particulates and provide with a strong tube to barrel bond.
A method for the production of glass stopcocks is described in U.S. Pat. No. 2,648,179 to Milton Manes, et al. Other methods and apparatuses for perforating and tubulating glass bodies is described in U.S. Pat. No. 2,146,572 to Clarence E. Hahn, et al., U.S. Pat. No. 2,272,927 to Luke L. Stager, U.S. Pat. No. 2,340,459 to William W. Eitel, U.S. Pat. No. 3,114,619 to Joseph E. Nitsche, et al. and U.S. Pat. No. 3,212,870 to Harry F. Condon. None of the present devices and methods satisfy the above needs nor attain the objects listed herein below.